Antenningstemperaturen

Antenningstemperaturen, often translated as antenna temperature, is a concept used in radio astronomy and radiometry. It represents the temperature of a blackbody that would produce the same amount of thermal noise power per unit bandwidth as an antenna system. This is a theoretical construct rather than a physical temperature of the antenna itself.

The antenna temperature is a measure of the noise power received by the antenna from all sources, including the celestial microwave background, radio sources in the sky, and the atmosphere. It also accounts for losses within the antenna system and the receiver. The measured power can be related to an effective temperature that would generate that power if it were solely due to thermal emission.

The unit for antenna temperature is typically Kelvin. It is crucial in radio astronomy to distinguish between the physical temperature of the antenna components and the antenna temperature, which reflects the radiometer's sensitivity to incoming noise. Understanding and accounting for antenna temperature is essential for accurately measuring and interpreting radio signals from astronomical objects and for calibrating radio telescopes.